<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <style>
    * {
        margin: 0;
        padding: 0;
    }

    h2 {
        text-align: center;
    }

    .box {
        width: 600px;
        margin: 50px auto;
        display: flex;
        font-size: 25px;
        line-height: 40px;
    }

    .qs {

        width: 450px;
        height: 40px;
        color: red;

    }

    .btns {
        text-align: center;
    }

    .btns button {
        width: 120px;
        height: 35px;
        margin: 0 50px;
    }
</style>
  <title>Document</title>
</head>
<body>
  <h2>随机点名</h2>
    <div class="box">
        <span>名字是：</span>
        <div class="qs">这里显示姓名</div>
    </div>
    <div class="btns">
        <button class="start">开始</button>
        <button class="end">结束</button>
    </div>
<script>
   const arr = ['马超', '黄忠', '赵云', '关羽', '张飞']
const qs = document.querySelector('.qs');
const start = document.querySelector('.start');
const end = document.querySelector('.end');
let i = 0
// i++
let item
let random
start.addEventListener('click', function(){

  item = setInterval(function(){
    random = Math.floor(Math.random()*arr.length)
qs.innerHTML = arr[random]
// qs.innerHTML = arr[i]
  }, 35)
 
 

})

end.addEventListener('click', function(){
  clearInterval(item)
  arr.splice(random, 1)
  if(arr.length <= 1){
    start.disabled = true
    end.disabled = true
  }
})


</script>
</body>
</html>